Lightweight visualization method of building information model based on Web3D

Abstract

The invention discloses a lightweight visualization method of building information model based on Web3D. By parsing the EXPRESS language description file which defines the IFC standard, the method ofextracting all kinds of information from the IFC file is established, and the information for 3D visualization is extracted at the same time. Through the transformation of geometric expression and thecalculation of rotational position matrix, the original 3D visualization information is transformed into the rendering data which can be rendered by a WebGL graphics engine. Then, combined with the building shape characteristics, the original multi-branch tree algorithm is improved to create a hybrid index based on building indoor and outdoor space partition and multi-branch tree forest. Finally,based on the hybrid spatial index, using the technology of view elimination, occlusion elimination, multi-threading and cache management, in the WebGL-based three-dimensional interactive graphics application, the rapid scheduling of three-dimensional model data between the browser and the server is realized. This method has the advantages of good lightweight performance, cross-platform and high computational efficiency.

Description

technical field [0001] The invention relates to the technical field of building information model and Web3D, in particular to a lightweight visualization method of building information model based on Web3D. Background technique [0002] Building Information Modeling (Building Information Modeling, BIM), as the data bearing platform and business connection hub of building information, is the basic configuration and core application of building life cycle management. The use of Web3D technology to process and analyze BIM information is the basis and premise of the application of architectural process visualization collaborative design, distributed processing and mobile computing. IFC is an international standard for the organization, presentation and exchange of BIM information. IFC-based BIM information has factors such as large data volume, complex structure, and high redundancy, and the real-time performance of direct visualization on the Web page is very weak, which canno...

AI Technical Summary

Problems solved by technology

Due to the large data redundancy in the OBJ format, the visualization loading speed is slow; there are also some methods that use the original multi-tree space division method to process the three-dimensional space, destroying the integrity of the three-dimensional object, increasing the drawing and Rendering calculation complexity; occlusion fusion is an indispensable step in the usual occlusion culling algorithm, and the calculation speed is usually slow if the CPU is used for calculation; although the calculation speed is fast with the GPU, most browsers do not support the latest directly calling the GPU to do occlusion queries function of

Therefore, the existing BIM lightweight visualization technology is usually inefficient, incompatible and one-sided

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